Doc generation is failing

[ablaom]

Locally I get this:

┌ Error: failed to run `@example` block in src/index.md:66-74
│ ```@example example1
│ RandomForestRegressor = @load RandomForestRegressor pkg=DecisionTree
│ forest = RandomForestRegressor(rng=rng)
│ rfe = RecursiveFeatureElimination(
│     model = forest, n_features=5, step=1
│ ) # see doctring for description of defaults
│ mach = machine(rfe, X, y)
│ fit!(mach)
│ ```
│   exception =
│    ArgumentError: Package MLJDecisionTreeInterface not found in current path.
│    - Run `import Pkg; Pkg.add("MLJDecisionTreeInterface")` to install the MLJDecisionTreeInterface package.

[ablaom]

In CI a different error is reported:

ERROR: ArgumentError: Package MLJBase not found in current path.
[15](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:16)
- Run `import Pkg; Pkg.add("MLJBase")` to install the MLJBase package.
[16](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:17)
Stacktrace:
[17](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:18)
 [1] macro expansion
[18](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:19)
   @ ./loading.jl:1772 [inlined]
[19](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:20)
 [2] macro expansion
[20](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:21)
   @ ./lock.jl:267 [inlined]
[21](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:22)
 [3] __require(into::Module, mod::Symbol)
[22](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:23)
   @ Base ./loading.jl:1753
[23](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:24)
 [4] #invoke_in_world#3
[24](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:25)
   @ ./essentials.jl:926 [inlined]
[25](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:26)
 [5] invoke_in_world
[26](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:27)
   @ ./essentials.jl:923 [inlined]
[27](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:28)
 [6] require(into::Module, mod::Symbol)
[28](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:29)
   @ Base ./loading.jl:1746
[29](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:30)
 [7] top-level scope
[30](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:31)
   @ none:4
[31](https://github.com/JuliaAI/FeatureSelection.jl/actions/runs/9375448971/job/25813583816?pr=11#step:6:32)
Error: Process completed with exit code 1.